Orion spacecraft design as of January 2013 (Wikimedia)

NASA is currently on the hot seat after it decided to bar Chinese scientists to an upcoming conference in November. China has cried discrimination. Some U.S. scientists likewise expressed disgust.

NASA explained it based its restrictive decision on a 2011 law which stated that NASA funds cannot be used in works in collaboration with China, nor to host Chinese visitors to space agency facilities in the U.S. It was signed no less than by President Barack Obama.

But Frank Wolf, the U.S. congressman who wrote the law, said the regulation had been wrongly interpreted.

The law "primarily restricts bilateral, not multilateral, meetings and activities with the Communist Chinese government or Chinese-owned companies," a letter issued by Mr Wolf's office to NASA Administrator Charles Bolden on Tuesday.

"It places no restrictions on activities involving individual Chinese nationals unless those nationals are acting as official representatives of the Chinese government."

NASA insignia (Wikimedia)

The decision to bar the Chinese contingent therefore was "inaccurate," Mr Wolf said.

The restriction to enter the Second Kepler Science Conference on exoplanets at California's Ames Research Center from Nov 4 to 8 has expectedly angered China.

"I have read relevant reports and also noticed that this discriminative action has met with opposition and sparked a boycott by US and Western scientists," Hua Chunying, Chinese foreign ministry spokeswoman, said at a regular press briefing. "We believe that academic or scientific activities should not be politicized," she added.

Gong Li, director of the Institute of International Strategic Studies of the Party School of the Communist Party of China Central Committee, said the focus of the conference is far from the Earth, and relating U.S. national security concerns with the conference is a "Cold War mentality".

"The US took similar actions against the former Soviet Union during the time of the Cold War," Gong Li, director of the Institute of International Strategic Studies of the Party School of the Communist Party of China Central Committee, told People's Daily. "I regret to see the U.S. backtrack to such a mentality in international technological exchanges today."

The bill, he said, utterly showed there are many American politicians such as Mr Wolf who are "profoundly nervous about China's development."

"Space technology cooperation benefits both countries, especially when China is no longer an underdeveloped player in this sector. Refusal of an exchange with Chinese scientists is indeed a loss for the US. I hope they can change this mindset," he said.

NASA's discriminatory stand has forced scientists from Europe and home turf U.S. to boycott the conference. "The conference itself should not be politicized," Ms Chunying said.

Among those leading the boycott are Geoff Marcy, an astronomy professor at the University of California, Berkeley and Debra Fischer, an astronomy professor at Yale University.

"In good conscience, I cannot attend a meeting that discriminates in this way. The meeting is about planets located trillions of miles away, with no national security implications," Mr Marcy wrote in an email to the organisers.

The International Space Station, 2011 (Wikimedia)